Method:For Chocolate-Peppermint Ganache:
Place chocolate in medium-sized bowl. Bring heavy cream just to
boil and pour over chocolate. Let sit for two minutes, then stir
to combine. Stir in peppermint extract. Refrigerate until firm,
about 4 hours.

For Triple Chocolate Shortbread Cookies:
In bowl of standing mixer fitted with paddle attachment, combine
butter, brown sugar and granulated sugar until fluffy. Add egg and
vanilla and beat until combined. In separate bowl, combine flour,
cocoa, baking soda and salt. Add to mixer and mix until just combined.
Scrape sides of bowl at least once. Add white and bittersweet chocolates
and mix until chocolates are evenly distributed.

Between layers of plastic wrap, roll dough out to 1/8 inch thick.
Peel off top layer of plastic and place back on dough. Flip dough,
peel plastic off what is now top. Cut cookies with 2 inch fluted
cookie cutter. Place about ½ inch apart on 2 or 3 cookie
sheets lined with parchment paper. Re-roll scraps and repeat. There
should be at least 60 cookies. Refrigerate at least 1 hour.

Preheat oven to 325°F. Bake cookies, one sheet at a time, 6
minutes each. Cookies will seem underdone, with no crunch. Let sit
10 minutes, then transfer to a rack to finish cooling. Let firm
up for at least 1 hour.

For White Modeling Chocolate:
In double boiler or bowl set over simmering water, melt white chocolate.
Remove from heat and stir in corn syrup. Continue stirring until
chocolate thickens and becomes sticky. Wrap tightly in plastic and
let rest two hours at room temperature.

Pull off two 1 ounce chunks (about 1 Tablespoon each) of modeling
chocolate. Using gloves, massage a few drops red food coloring into
one chunk. Repeat with other chunk, using green food coloring. Divide
remaining plain modeling chocolate into quarters. Flatten two quarters
into rough squares about sandwich bread thickness. Flatten red chocolate
into a square the same size. Sandwich the red square between the
two plain squares. Make five equal length strips. Turn on their
sides to expose colored stripes and gather all strips together.
Gently work together into a lump. Repeat with green chocolate and
remaining quarters.

Sprinkle small amount of powdered sugar onto pastry mat or silpat
and gently roll red lump to 1/8 inch thickness. Using a 2 –
3/8 inch size round fluted cookie cutter, cut as many circles of
dough as you can. Pull up scraps and gently reroll and cut until
you’ve used up all the chocolate. Be careful not to overwork
the chocolate or it will lose its marbled pattern. Repeat with green
lump.

To Assemble:
Spread scant Tablespoon of Chocolate-Peppermint Ganache on underside
of Triple Chocolate Shortbread Cookie, leaving small amount of ganache
on spreader. Place another cookie on top of ganache, and dab rest
of ganache on top. Gently place a circle of red or white chocolate
on ganache and press so that chocolate adheres. Repeat with remaining
cookies, ganache & modeling chocolate.